Conventionally, in semiconductor implementation, a flip chip method is carried out, wherein a side of an IC (Integrated Circuit) on which electrodes (bumps) are formed and the side of a substrate on which electrodes (electrode pads) are formed are opposed to each other to electrically connect the bumps of the IC chip and the electrode pads of the substrate.
In this flip chip method, in order to externally protect the connection between the electrodes and to relax the stress attributable to the difference in the linear expansion coefficients of the IC chip and the substrate, a liquid thermosetting adhesive called an underfill agent is poured between the semiconductor chip and the substrate and allowed to be cured, usually after the electrodes are connected.
In recent years, miniaturization of IC chips has been rapidly advanced. With this advancement, pitches between adjoining electrodes and gaps between semiconductor chips and substrates tend to be increasingly narrower. Thus, if an underfill agent is poured in between an IC chip and a substrate by using the capillarity phenomenon, problems are caused, such as occurrence of a void or a long time required for pouring an underfill agent.
Thus, the so-called pre-placement method has be attempted, wherein a liquid adhesive, such as NCPs (Non Conductive Pastes) and non-underfill agents, or a film adhesive, such as NCFs (Non Conductive Films) is applied or adhered on a substrate in advance, and a resin is then cured with thermocompression from a thermocompression bonder to thereby connect the bumps of an IC chip and the electrode pads of a substrate.
Also, a method for applying an NCP on a wafer before cutting into IC chips and half-curing the NCP, and the so-called pre-adhesion method, wherein an NCF is adhered, the thickness of the wafer is then thinned by back-grinding, and the wafer is individualized into pieces by dicing to provide IC chips having an NCF, one of which is implemented on an organic substrate and the like with a flip chip bonder, have been carried out.
For example, Patent Document 1 discloses a pre-adhesion method using ACFs (Anisotropic Conductive Films). Also, Patent Document 2 discloses a method for pre-laminating an NCF on a wafer. Also, Patent Document 3 discloses that the thickness of an NCF is set to the height of a bump±30 μm.